The study of electronic, structural, mechanical, and piezoelectric properties of bulk NbOX2 (X = Cl, Br, and I) using density functional theory

Abstract: In this work, we have performed a comprehensive study of dielectric materials NbOX2 (X=Cl, Br, and I) within the framework of density functional theory, incorporating both conventional and hybrid functionals.Our studies focus on the structure, electronic, elastic, and piezoelectric properties. Piezoelectricity is an innovative avenue to extract energy by manipulating the material's structures via mechanical stress. The use of non-lead-based material for piezoelectricity added an advantage of a greener approach. Among the investigated materials, bulk NbOI2 exhibits the highest piezoelectric response of 6.32 C/m$^2$, which is around 31% higher than NbOCl2, NbOBr2 and even lead zirconate titanate.